Locking device for platform rockers



Dec. 25, 1951 Filed June 14, 1950 M. FOX

LOCKINGA DEVICE FOR PLATFORM ROCKERS 2 SHEETS- SHEET l f .7% [far/zeges Dec. 25,l 1951 Y M, FOX r2,580,165

4LOCKING DEVICE FOR PLATFORM ROCKERS Filed June 14, 1950 2 SHEETS-o 2 Wm, l ofney Patented Dec. 25, 1951 LOCKNG DEVICE FOR PLATFORM'ROCKER Martin Fox, Chicago, Ill., assigner to-The 'Seng Company, a corporationf AIllinois This invention relates to platform rockersjand more particularlyto a `locking device for holding the chair -in a desired angular relation t its platform.

The -gprimary object of the `invention :is itoprovide a simple and effective locking device for a conventional platform rocker, whereby the occupant may rock the chair back to a desired angle and move a lever which will hold the chair in that position and prevent it from rocking until the lock is released.

A further object of the invention is to provide an improved clamping member in which a metalto-metal contact between the sliding means is avoided to eliminate noise and reduce wear so that it is practically negligible. This is done by using a compressible member of organic material, preferably molded nylon.

Another object of the invention is to provide a rounded socket in the clamping member for a ball shaped compressible member of nylon, so that the rod which is gripped may be straight and does not need to be curved to accommodate the rocking movement of the chair. This swivel mounting facilitates installation, because it is not necessary to have the clamping member aligned exactly above the hinged supporting bracket for the rod.

The present device is an improvement over the one shown in my 'application Serial No. 86,354, filed April 8, 1949, which has become abandoned.

The invention is illustrated in a preferred embodiment in the accompanying drawings in which- Fig. 1 is a side elevational View of a conventional platform rocker equipped with the improved locking device; Fig. 2, a vertical sectional view, taken as indicated at line 2-2 of Fig. 1; Fig. 3, a fragmentary sectional view, taken as indicated at line 3-3 of Fig. 2; Fig. 4, an elevational view of the supporting bracket for limiting the oscillation of the cam shaft; Fig. 5, a fragmentary top plan view, taken as indicated at line 5--5 of Fig. 3; Fig. 6, a top plan view of the compressible member; and Fig. 7, a fragmentary front elevational View of the same.

In the embodiment illustrated, a supporting platform is provided with side bars 9, which are secured together by a front cross-bar lll and a rear cross-bar il. A rocking chair I2 has arms i3 and a seat I 4 provided with curved. rocker arms l5 adapted to move on the bars 9 of the platform. Springs l5 connect the two parts and urge the rocking chair to its upright position, indiindicated by 'the "dotted lines. is all conventional.

5 claims. (o1. 155-72) cated .in Fig.v 1, but permit it to be inclined-as This lstructure AThe `locking device lincludes a metalrod I1 'which makes 'a hinged connection VI8 Iat its lower end with a bracket I9 attached to thefrontcrossbar Ill by screws 20.

A clamping member 2| is generally U-shaped and is secured to the front cross-bar 22 of the chair by means of screws 23. As best seen in Figs. 3 and 5, the side walls of the clamping member are struck outwardly, as indicated at 2d,

on a spherical radius, to provide a rounded socketV for the compressible member 25 which is generally of spherical shape but has a forwardly presented flat face 26, and its opposite ends are attened, as indicated at 21, around an aperture 28 which receives the rod l1. The side walls of the clamping member are apertured to provide bearings at 29 for a cam shaft 3B.

The cam shaft has an eccentric portion 3| within the arms of the clamping member which is adapted to bear against a U-shaped keeper 32 which bears against the at face 26 of the nylon member and also embraces the end portions 21. The ends of the keeper 32 are cut away to clear the cam shaft I1 by about a thirty-second of an inch.

The cam shaft extends out through the side frame of the chair, and has an operating arm Y 33 to which a handle 34 may be attached. The mid portion of the shaft is supported by a slotted bearing 35 which is fastened `to the cross-bar 22 by screws 36. As best shown in Figs. 2 and 4, the shaft has a detent 31 which extends into the slot 38 in the hinge member and limits the oscillation of the cam shaft.

The compressible member 25, as shown in Fig. 6,V may be slotted, as indicated at 25a, although this is not absolutely necessary if nylon is used. Nylon makes an excellent anti-friction material and, due to its elasticity, is preferred in the present device.

In operation, the occupant of the chair merely leans back to a desired angle and then turns the handle 34 upwardly into locking position. The movement of the eccentric causes the member 25 to be compressed and tightly grip the rod I1. If it is ,desired to rock, the handle is released and the rod l1 will slide back and forth through the clamping member without noise, as there is no metal to metal contact.

The foregoing detailed description is given for clearness of understanding only, and no unnecessary limitations should be understood therefrom,

2,580,165 3 4 for some modications will be obvious to those 4. A device as specied in claim 1, in which the skilledinthe art. rod is straight and makes a hinged connection I claim: with the mounting bracket, the clamping member 1. A locking device for releasably securing a rocking chair against rocking movement on its platform, comprising: a rod provided at its lower end with a mounting bracket adapted to be attached to the front cross-bar of a rockerplatform; a clamping member, adapted to be secured to the front cross-bar of a rocking chair, and provided with a laterally extending bearing to receive a cam shaft; a compressible member mounted in said clamping member and apertured to receive said rod; and a cam shaft journalled in said bearing and provided at one end with an operating arm, said shaft having an eccentric portion positioned to compress said compressible. member to grip the rod When said. arm is turned rod is straight and makes a hinged connection with the mounting bracket, and the compressible member is made of nylon and is swivelly mounted in the clamping member.

has a rounded socket, the compressible member is made of nylon and is generally spherical in shape, and is swivelly mounted in said socket.

5. A device as specified in claim 1, in which the compressible member is generally spherical With la at face towards the cam shaft, and a U-shaped keeper is interposed between the eccentric portion of said shaft and said member so as to embrace said at face and opposite portions of the apertured ends of the member.

MARTIN FOX.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

